Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

NPA: 301 [Rate centres in NPA 301] [Dial plan for NPA 301]

NXX: 400

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-400 A Washington Zone 2 MD BTHSMDWWDS0  9212 VERIZON MARYLAND, INC. 236      
301-400 0 Washington Zone 2 MD   9212 VERIZON MARYLAND, INC. 236   2010-06-05   
301-400 1 Washington Zone 2 MD   9212 VERIZON MARYLAND, INC. 236   2010-06-05   
301-400 2 Washington Zone 2 MD   9212 VERIZON MARYLAND, INC. 236   2010-06-05   
301-400 3 Washington Zone 2 MD   9212 VERIZON MARYLAND, INC. 236   2010-06-05   
301-400 4 Washington Zone 2 MD   9212 VERIZON MARYLAND, INC. 236   2010-06-05   
301-400 5 Washington Zone 2 MD   9212 VERIZON MARYLAND, INC. 236   2010-06-05   
301-400 6 Washington Zone 2 MD   9212 VERIZON MARYLAND, INC. 236   2010-06-05   
301-400 7 Washington Zone 2 MD   9212 VERIZON MARYLAND, INC. 236   2010-06-05   
301-400 8 Washington Zone 2 MD   9212 VERIZON MARYLAND, INC. 236   2010-06-05   
301-400 9 Washington Zone 2 MD   9212 VERIZON MARYLAND, INC. 236   2010-06-05   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

Sponsored by: VoIP Much Phone Company

Like this site? We accept donations via PayPal.